The objective of this proposal is to develop and evaluate an immunodiagnostic method for the detection of prostatic cancer. We will search for prostate-associated (specific) antigens/enzymes from prostatic glands and blood of patients with prostatic carcinoma. The antigens (and/or enzymes) will further be purified, characterized and specific immune sera will be raised in rabbits and/or goats. Using the specific antiserum and the purified antigens (or enzymes), an immunoassay procedure will be developed for the determination of antigen (or enzyme) levels in the blood of patients. Usefulness of the prostatic tumor antigen (or enzyme) as a marker for the presence of early tumor and for the evaluation of treatment will be determined.